A small battery light or low-torque driver is okay, for small jobs.
I've never liked battery operated hand or system tools, for several reasons:
1) the initial cost of tool and battery and charger is much higher than an ac tool and the extension cords.
2) A battery losses power and/or goes bad, and will cost you more in replacements over the life of the tool than an AC tool
3) With medium to large work sites, there will be recharging stations that must be manned by a battery runner/gopher, over and above the regular helpers/gophers.
4) Overall costs in electricity, for you and the customer, will be higher with a battery system.

I've not found battery tools to be cost effective or efficient.
They cost too much for me, my employees, and clients.

A small battery light or low-torque driver is okay, for small jobs.
I've never liked battery operated hand or system tools, for several reasons:
1) the initial cost of tool and battery and charger is much higher than an ac tool and the extension cords.
2) A battery losses power and/or goes bad, and will cost you more in replacements over the life of the tool than an AC tool
3) With medium to large work sites, there will be recharging stations that must be manned by a battery runner/gopher, over and above the regular helpers/gophers.
4) Overall costs in electricity, for you and the customer, will be higher with a battery system.

I've not found battery tools to be cost effective or efficient.
They cost too much for me, my employees, and clients.

The guys on my crews all use cordless power tools, and we're building a bridge. They have those power converters installed in their trucks and they have a few batteries on charge at all times. Quick swap, no muss no fuss. The new batteries out now are far better than the old ones.

Each to his own I guess, but having to fire up and haul a generator around, messing with cords, et cetera seems so '20th century' at this point.

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The guys on my crews all use cordless power tools, and we're building a bridge. They have those power converters installed in their trucks and they have a few batteries on charge at all times. Quick swap, no muss no fuss. The new batteries out now are far better than the old ones.

Each to his own I guess, but having to fire up and haul a generator around, messing with cords, et cetera seems so '20th century' at this point.

I understand your point, especially with building something that doesn't have any power to it. But how close can they get the trucks to their work position, and is it cost effective to have a union worker leave the job site to change out a battery. don't you hire gophers/runners for these tasks?

Granted, most all my work has had power available at the work, it's just stepping down the voltage to something usable.
I carried around several battery operated electronics, multi-meters, portable o'scope, a/d converters, tracers...
But none of them required the high current needed that your talking about.
Guess that's my bias

But how close can they get the trucks to their work position, and is it cost effective to have a union worker leave the job site to change out a battery. don't you hire gophers/runners for these tasks?

Show some respect; They call them Grunts ...

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